I answer that, All are agreed in saying that original sin was remitted in circumcision. But some said that no grace was conferred, and that the only effect was to remit sin. The Master holds this opinion (Sent. iv, D, 1), and in a gloss on Romans 4:11. But this is impossible, since guilt is not remitted except by grace, according to Romans 3:2: "Being justified freely by His grace," etc.
Wherefore others said that grace was bestowed by circumcision, as to that effect which is the remission of guilt, but not as to its positive effects; lest they should be compelled to say that the grace bestowed in circumcision sufficed for the fulfilling of the precepts of the Law, and that, consequently, the coming of Christ was unnecessary. But neither can this opinion stand. First, because by circumcision children. received the power of obtaining glory at the allotted time, which is the last positive effect of grace. Secondly, because, in the order of the formalcause, positive effects naturally precede those that denote privation, although it is the reverse in the order of the material cause: since a form does not remove a privation save by informing the subject.
Consequently, others said that grace was conferred in circumcision, also as a particular positive effect consisting in being made worthy of eternal life; but not as to all its effects, for it did not suffice for the repression of the concupiscence of the fomes, nor again for the fulfilment of the precepts of the Law. And this was my opinion at one time (Sent. iv, D, 1; 2, 4). But if one consider the matter carefully, it is clear that this is not true. Because the least grace can resist any degree of concupiscence, and avoid every mortal sin, that is committed in transgressing the precepts of the Law; for the smallest degree of charity loves God more than cupidity loves "thousands of gold and silver" (Psalm 118:72).
We must say, therefore, that grace was bestowed in circumcision as to all the effects of grace, but not as in Baptism. Because in Baptism grace is bestowed by the very power of Baptism itself, which power Baptism has as the instrument of Christ's Passion already consummated. Whereas circumcision bestowed grace, inasmuch as it was a sign of faith in Christ's future Passion: so that the man who was circumcised, professed to embrace that faith; whether, being an adult, he made profession for himself, or, being a child, someone else made profession for him. Hence, too, the Apostle says (Romans 4:11), that Abraham "received the sign of circumcision, a seal of the justice of the faith": because, to wit, justice was of faith signified: not of circumcision signifying. And since Baptism operates instrumentally by the power of Christ's Passion, whereas circumcision does not, therefore Baptism imprints a character that incorporates man in Christ, and bestows grace more copiously than does circumcision; since greater is the effect of a thing already present, than of the hope thereof.